Frustrated by protracted negotiations with NRL club Parramatta, Israel Folau signed to make rugby union his third pro football code after feeling he had to settle his future and being impressed by new NSW Waratahs coach Michael Cheika.

Announcing his one-year deal to play Super Rugby with the Waratahs on Tuesday, Folau said he'd made no promises to Parramatta coach Ricky Stuart, who has declared bitterly that the Eels are "genuinely better off without him".

While Folau told Parramatta last Friday he would not be returning to the NRL, Cheika revealed he'd first started meeting with Folau three weeks ago.

The relationship clearly blossomed as Folau so Cheika so impressed him that he was the main reason why he agreed join the Tahs, with aspirations to go on and play for the Wallabies.

The deal ends a month of intense speculation about the 23-year-old former rugby league Test star's future since he cut short his multi million dollar, four-year deal with AFL club Greater Western Sydney citing a lack of passion for the game after he struggled to adapt.

Folau said his first choice when leaving GWS was to return to the NRL.

And he said the last few days since he walked away from the Eels' talks had been tough after he was branded a money-hungry mercenary in sections of the media.

He insisted the move to rugby union wasn't a money-driven venture, noting that if it was only about money he would have stayed for the last two years of his AFL deal.

"It (rugby union) kind of came out of nowhere," said Folau.

"It wasn't on the cards (upon leaving GWS), but when I thought about it more over time it started to be a bit clearer to me.

"When I met with Michael (Cheika) it felt good and right for me, the type of person that he was.

"I spoke to Ricky (Stuart) about the possibility of coming back to play rugby league. But throughout the times that we were dealing with them, things didn't come to plan for both parties.

"I couldn't wait any longer, sitting around. It was uncertain for my future, so I had to move forward.

"I won't go into detail what happened. But obviously things didn't work out the way I'd like them to. That's why I'm here today.

"I met with Parramatta on Friday, met them face to face and told them how I was feeling, I have nothing to hide."

Having only played a handful of school games at inside centre, Folau said he came to rugby union as a newcomer but was already eyeing off a Wallabies berth.

"It was definitely something that I was thinking about. Obviously it'd be great to represent your country and to play against the likes of the All Blacks is something that's appealing.